Tropical Storm Nolo Advisory Number 14

Public advisory

Central Pacific Hurricane Center · issued Sep 24, 2:49 AM UTC · source


000
WTPA32 PHFO 240249
TCPCP2
 
BULLETIN
Tropical Storm Nolo Advisory Number  14
NWS Central Pacific Hurricane Center Honolulu HI   EP152026
Issued by NWS National Hurricane Center Miami FL
500 PM HST Wed Sep 23 2026
 
...TROPICAL STORM NOLO HOLDING STEADY AND IS EXPECTED TO TURN
NORTHWARD TONIGHT...
...HURRICANE WATCH REMAINS IN EFFECT FOR HAWAII COUNTY...
 
 
SUMMARY OF 500 PM HST...0300 UTC...INFORMATION
----------------------------------------------
LOCATION...14.7N 155.9W
ABOUT 295 MI...480 KM S OF SOUTH POINT HAWAII
ABOUT 475 MI...765 KM SSE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
 
None.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
 
A Hurricane Watch is in effect for...
* Hawaii County
 
A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.
 
Interests elsewhere in the Hawaiian Islands should closely monitor
the progress of this system.
 
For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 500 PM HST (0300 UTC), the center of Tropical Storm Nolo was
located near latitude 14.7 North, longitude 155.9 West. Nolo is
moving toward the west-northwest near 6 mph (9 km/h). A sharp turn 
to the north and north-northeast is expected late tonight, with this 
motion continuing through the end of the week. On the forecast 
track, the system is expected to approach the Big Island of Hawaii 
on Friday and Saturday.
 
Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. 
Nolo is forecast to become a hurricane by Thursday night and could 
become a major hurricane by the weekend.
 
Tropical-storm-force winds extend outward up to 80 miles (130 km)
from the center.
 
The estimated minimum central pressure is 1002 mb (29.59 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
Key messages for Nolo can be found in the can be found in the
Tropical Cyclone Discussion under AWIPS header HFOTCDCP2 and WMO
header WTPA42 PHFO.
 
WIND: Hurricane conditions are possible in the watch area starting
as early as Friday night.
 
RAINFALL: Tropical Storm Nolo will produce rainfall totals of 15 to
20 inches across the Big Island with maximum amounts of 35 inches.
This rainfall may produce catastrophic life-threatening flooding and
mudslides, especially in areas of steep terrain. Rainfall totals of
5 to 10 inches with maximum amounts of 20 inches expected across
Maui. Life-threatening flooding and mudslides possible across Maui,
especially in areas of high terrain. Across the remainder of the
Hawaiian Islands, rainfall totals of 1 to 3 inches with maximum
amounts of 6 inches are expected with isolated flooding possible.
 
For a complete depiction of forecast rainfall associated with
Tropical Storm Nolo, please see the National Weather Service Storm
Total Rainfall Graphic available at
hurricanes.gov/graphics_cp2.shtml?rainqpf
 
STORM SURGE: The combination of a dangerous storm surge and the tide
will cause normally dry areas near the coast to be flooded by rising
waters moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...
 
Hawaii County...1 to 3 ft
 
The deepest water will occur along the immediate coast near and to
the right of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.
 
For a complete depiction of areas at risk of storm surge
inundation, please see the National Weather Service Peak
Storm Surge Graphic, available at
hurricanes.gov/graphics_cp2.shtml?peakSurge.
 
SURF: Swells generated by Nolo are expected to reach exposed east
and south-facing shores of the Big Island by Friday, spreading
westward and building through the weekend. These swells are likely
to cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.
 
 
NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM HST.
Next complete advisory at 1100 PM HST.
 
$$
Forecaster Gibbs
 

Forecast discussion

Central Pacific Hurricane Center · issued Sep 24, 2:52 AM UTC · source


000
WTPA42 PHFO 240252
TCDCP2
 
Tropical Storm Nolo Discussion Number  14
NWS Central Pacific Hurricane Center Honolulu HI   EP152026
Issued by NWS National Hurricane Center Miami FL
500 PM HST Wed Sep 23 2026
 
Nolo's convective organization has improved slightly during the past 
several hours, with persistent deep convection within a curved band 
wrapping into the circulation from the north around the western 
semicircle. The latest subjective Dvorak intensity estimates from 
JTWC and HFO are both T2.0/30 kt, while objective intensity 
estimates range from 30 to 40 kt. Given the improved convective 
organization and the higher objective estimates, the initial 
intensity was increased to 40 kt in the 2 PM HST intermediate 
advisory and is maintained for this advisory.
 
Nolo is moving west-northwestward, with an initial motion of 285/5 
kt. A weakening subtropical ridge to the north should allow 
Nolo to slow down and turn northward tonight into Thursday, followed 
by a north-northeastward motion as an upper-level trough deepens 
northwest of the Hawaiian Islands. As the trough moves westward and 
the subtropical ridge rebuilds north of Hawaii, Nolo is forecast to 
make a sharp westward turn Friday night into Saturday. The latest 
GDMI and HCCA guidance has shifted slightly to the left, taking Nolo 
farther south of the Big Island. The NHC track forecast reflects a 
blend of the previous forecast and these aids, and shows Nolo 
passing about 85 n mi south of the Big Island on Saturday, then 
about 215 n mi south of the smaller Hawaiian Islands during the 
latter portion of the weekend. However, uncertainty remains 
regarding exactly when and where the sharp westward turn will occur, 
with the ECMWF remaining on the right side of the guidance envelope 
and bringing Nolo closer to the islands.
 
Environmental conditions remain favorable for strengthening, with 
very warm sea surface temperatures and plenty of mid-level moisture 
along the forecast track. However, around 10 kt of easterly vertical 
wind shear may temper the rate of intensification during the next 24 
to 36 h. As the shear relaxes and Nolo continues to develop an inner 
core, a faster rate of intensification is forecast while the cyclone 
moves northward to north-northeastward during the next couple of 
days. These conditions could support rapid intensification, and Nolo 
is forecast to become a hurricane by Thursday night and reach major 
hurricane strength on Saturday as it passes south of the Big Island. 
The latest NHC intensity forecast hovers near the upper end of the 
guidance envelope throughout the forecast period.
 
Key Messages:
 
1. Tropical Storm Nolo is expected to strengthen into a hurricane
by Thursday night as it turns northward, potentially making its
closest approach to the Big Island of Hawaii on Saturday. A
Hurricane Watch remains in effect for the Big Island, and residents
there should follow advice given by local officials, including
evacuating if told to do so.

2. The time to prepare for significant heavy rain and flooding
impacts on the Big Island is now, as heavy rain becomes more likely
by Thursday and Friday. Periods of heavy rain are likely to
continue across the Big Island and Maui through the weekend.
Life-threatening, catastrophic flooding and mudslides are possible,
especially in areas of steep terrain across the Big Island and
Maui. Across the remainder of Hawaii, lesser rainfall totals are
expected, with isolated flooding possible.

3. Large and damaging waves are possible along the coast of the
Big Island into the weekend.

4. Interests elsewhere in Hawaii should closely monitor the latest
forecast updates and ensure that they have their preparedness plans
in place.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  24/0300Z 14.7N 155.9W   40 KT  45 MPH
 12H  24/1200Z 14.8N 156.0W   50 KT  60 MPH
 24H  25/0000Z 15.4N 155.8W   60 KT  70 MPH
 36H  25/1200Z 16.2N 155.3W   70 KT  80 MPH
 48H  26/0000Z 17.1N 155.0W   80 KT  90 MPH
 60H  26/1200Z 17.5N 155.1W   90 KT 105 MPH
 72H  27/0000Z 17.4N 156.2W  100 KT 115 MPH
 96H  28/0000Z 17.5N 158.6W  105 KT 120 MPH
120H  29/0000Z 18.9N 162.1W  100 KT 115 MPH
 
$$
Forecaster Gibbs